莲草直胸跳甲在几种非靶标植物上的适合度比较

莲草直胸跳甲是防治入侵杂草喜旱莲子草的引进天敌,为检测莲草直胸跳甲对非靶标植物的影响,选取了29种具有代表性的植物对该天敌进行了3种选择和1种非选择性压力的测试.在全组植物或移除喜旱莲子草组中,莲草直胸跳甲成虫和幼虫对喜旱莲子草和非靶标近缘种莲子草的取食面积均显著大于其它非靶标植物,幼虫还可取食非靶标植物若蘧、反枝苋等;成虫在无喜旱莲子草时可取食若蘧和甜菜.当移除喜旱莲子草和莲子草时,成虫和幼虫对若蘧和甜菜的取食面积分别提高22.33、4倍和1.76、16.42倍.在非选择测试中,成虫和幼虫对喜旱莲子草和莲子草的取食显著高于其它组,其它植物均不能满足其正常发育和生存.研究表明,莲草直胸跳甲对莲子草属植物的适合度最高.

The fitness of Agasicles hygrophila on several non-target plant species

Agasicles hygrophila was an introduced natural enemy for bio-control of the invasive weed Alternanthera philoxeroides in China. Based on three kinds of choices and one limited condition, 29 representative plant species were selected to analyze A.hygrophila's feeding fitness to test the risk of A.hygrophila on non-target plant species. The results showed that the adults and larvae mainly fed on their host plant A.philoxeroides and non-target plant A.sessilis, and the feeding areas were significantly larger than those of the other groups; the larvae also fed on non-target plants Beta vulgaris var.cicla, Amaranthus retroflexus, etc., at all choice conditions. The feeding scope of adults was narrower than that of the larvae which mainly fed on non-target plants B.vulgaris var. cicla and B.vulgaris. The feeding areas of adults and larvae on B.vulgaris var. cicla and B.vulgaris rose by 22.33, 4 fold and 1.76, 16.42 fold, respectively, and the larvae enlarged their feeding scope while the A.philoxeroides and A.sessilis were removed. The non-choice tests showed that adults and larvae could only survive and develop on A.philoxeroides and A.sessilis and significant differences were observed among the feeding areas on the other plants. The results indicated that the host specific fitness of Alternanthera plants was the highest among the plants tested.